1. Field of Invention
The present invention relates to a vise clamp
2. Related Prior Art
A vise clamp is primarily used in places where a vise cannot be used. For example, in processing planks, a vise clamp can be moved to various positions as desired by a user, but a vise cannot. A C-shaped vise clamp includes a body, a stationary jaw formed on the body, a screw installed on the body, and a movable jaw with a screw hole for receiving the screw. By means of rotating the screw, the movable jaw is moved up and down in order to clamp. For not including a retaining device, the C-shaped vise clamp often looses when subject to vibration. The following steps of the operation are thus affected. Moreover, the movable jaw can only be moved by means of rotating the screw, the speed of clamping is slowed. The smoothness of the operation is affected.
There has been devised a new C-shaped vise clamp including a stationary jaw, a movable jaw installed on the stationary jaw, and a clamping device connected to the movable jaw. The clamping device includes a lever formed with a cam. A ratchet mechanism is provided between the lever and the movable jaw. A contact element is put against the cam. Wishing to clamp a workpiece, a user moves the movable jaw so that the movable jaw reaches the workpiece. The user pivots the lever. The cam pushes the contact element. Thus, vise clamp clamps the workpiece. The ratchet mechanism is supposed to retain the lever and therefore the contact element in position. The pivotal of the lever is faster than the rotation of a screw.
In the foregoing C-shaped vise clamp, the cam formed on the lever is used to clamp; however, it causes an inadequate stroke of the movement of the contact element and therefore an adequate clamping force. The clamping force is particularly inadequate when it is used to clamp an elastic workpiece. Moreover, the abutment of the cam against the contact element affects the position of the contact element so that the contact element may not fully contact a workpiece. Hence, the clamping is not stable. Hence, there is room for improvements.
The present invention is therefore intended to obviate or at least alleviate the problems encountered in prior art.